Beachgoers in Russia found themselves in the midst of a tactical maneuver by the world's largest class of hovercraft. A Russian defense ministry spokesperson said that the beach was on the territory of a Russian military base, and that he didn't know why there were civilians on the beach.

At least that's what hundreds of beachgoers near Kaliningrad learned when a nearly 200-foot-long hovercraft, spraying a plume of water 80-feet high, made an unexpected landing.

The hovercraft was very probably one of Russia's three Zubr-class landing vessels. The world's largest hovercraft, the Zubr, or Russian for "bison," can carry up to 130 tons of cargo, including up to 500 troops. Constructed in St. Petersburg, the Zubr is also used by the navies of Ukraine, China, and Greece.

Sky quotes a Russian military spokesman, who said that the vessel was performing tactical maneuvers in the Baltic Sea. He called the landing a "normal event."

"What people were doing at the beach on the territory of a military (base) is unclear," said the spokesman. Sky speculates that he might have been referring to a base that is several miles away from the beach.

What's also unclear is why the hovercraft, which can fly only a few feet above the water's surface, was carrying paratroopers.